Track type tractors, with a blade attached to the front thereof (e.g., bull dozers), are used to cut, lift or move material out of the ground or structures and to push the material to a new location. The amount of material that can be cut or moved is partly dependent and determined by vehicle weight, blade design, track-tread design, and the environment (coefficient of traction for the soil). For a given vehicle design, the primary large determinative variable is the condition of the soil, whether: wet/moist/dry, loose/compact, sand/clay, etc. This variable and types of soil condition have a significant impact on the effective coefficient of traction (COT). The higher the COT the more load the vehicle can push because it is easier to maintain traction (track tread engagement with the soil) before the vehicle loses traction with a “spinning out”. The term “track” as used herein includes tracks, treads and wheels on the vehicles subject to “slip” or loss of traction.
Prior art expedients, such as described in U.S. Pat. No. 7,340,339, involve local sensors or electronics which automatically limit fuel supply and/or limit torque, to, among other things, reduce stress in components to prevent component damage. None of these or other expedients of the prior art, describe devices or means, which enhance slippage control and smoothness of vehicle operation, without relying on actual vehicle speed measurement. In addition, the prior art has not disclosed or used expedients which permit the intervention of an operator to initiate or otherwise allow an operator, with microprocessor or electronic control to more closely enhance slippage control and smoothness of vehicle operation.